Willotjghby smith



UNITED STATES PATENT OFFICE.

WILLOUGHBY SMITH, OF WHARF ROAD, oITY EoAD, COUNTY OF MIDDLE- SEX, ENGLAND.

INSULATING ELECTRICAL CONDUCTORS AND A NEW COMPOUND SUITABLE TO BE USED FOR THIS AND OTHER PURPOSES,

SPECIFICATION forming part of Letters Patent No. 276,916, dated May 1, 1883.

Application filed March 19,1883. (No specimens.) Patented in England December 28, 1882, No. 6,196.

To all whom it may concern:

Be it known that I, \VILLOUGHBY SMITH, a subject of the Queen of Great Britain, residing at \Vharf Road, City Road, in the county of Middlesex, England, have invented certain new and useful Improvements in Insulating Electrical Conductors and a new Compound Suited to be Used for this and other Purposes, (for which I have received Letters Patent in Great Britain, No. 6,196, dated December 25, 1882,) of which the following is a specification.

This invention has for its object improvements in insulating electrical conductors and a new compound suited to be used for this and other purposes.

In insulating electrical conductors I take, by preference, gutta-percha of the cheaper sort, such as cannot be used alone in the ordinary process of covering wires, and Imix the guttapercha with finely-powdered bituminous coal. The coal, which should he of good quality, is ground and sifted through sieves, as flour is prepared. The admixture is made while the gutta-percha is being inasticated in the 0rdinary way in a masticatiug-machine, or by the use of rollers; or by other means the mixture may be brought about. The proportions may be varied, if the object be simply to improve the working of the composition through the covering-die. This object will befully attained by the addition ofone part, by weight, ofground coal to from ten to five ot' gutta-percha; but with the object of increasing the bulk of the compound, and to attain the maximum utility at a given cost, the ground coal may be used in the proportion of one part to two or three of gutta-percha, or even alarger proportion of ground coal may be employed.

The compound is applied to cover the wire or strand, serving'as the conductor, by pressing the compound out from a die, through which the wire or strand is also led. The compound is maintained in a plastic condition by heat, and the process is conducted in the same way as at present when covering wires or strands with gutta-percha.

By means of this invention electrical conductors may be well insulated at a much smaller cost than at present.

My compound of gutta-percha and ground coal can also advantageously be used to make battery-cells and like articles. It may be rolled into sheets and used as a substitute for vuloanite. For these purposes a compound consisting of one part of ground coal to three parts of gutta-percha is very suitable.

What I claim isl. Insulating electrical conductors by covering them, through a die, with a compound of gutta-percha and ground coal.

2. My new plastic insulating compound, consisting of gutta-percha and ground coal intimately mixed.

WILLOUGHBY SMITH.

Witnesses:

J OHN DEAN, J. WATT,

Both ofl? Gi'cccclzm'ch Street, London. 

